Field
Aspects of the present invention relate to an over voltage disconnect, e.g., for use with 277 volt (V) lighting systems.
Background of the Technology
A 277 V lighting system includes a shared circuit, one leg of the shared circuit being 277 V. In 277 V lighting systems having shared neutrals, there is a possibility of an over voltage condition, e.g., if that neutral connection is lost. In an over voltage condition, the voltage rises above the intended 277 V. The severity of the over voltage depends on the loading of the other phases in the system. Whereas older iron core “transformer” type ballasts and bulbs could handle or “absorb” the overage and remain functional afterward, newer lighting systems can be damaged by over voltages. Among other things, an over voltage can be destructive to newer switching type power supplies, ballasts, Light Emitting Diode (LED) drivers, etc. Newer, electronic based and/or switching type power supplies have a specific range of voltage that they are designed to accept. Voltages beyond that range will most likely result in some sort of failure that will render the corresponding lighting system useless.
Thus, in lighting systems having electronic based and/or switching type components such as LEDs or other similar solid state light emitters, a solution is needed to protect the lighting system from such over voltages.